Manufacture a helmet require some through engineering studies to make a Helmet capable to absorb impacts 5 time superior to what a human would support. Allows to save meny lives.

We can see all the manufacturing process at the factory in this video at the German Schubert factory. All helmets are manufactured with rigorous quality controls by high-end machinery.

But not satisfy with that, each 3000 helmets that they produce, try to break into pieces a dozen submitting them to hard impact proofs.

http://www.youtube.com/watch?v=aaNxco-JPTY